Method and means for dispersing foam

ABSTRACT

Foam is generated by mixing water, foam material, and compressed air under pressure. The foam is released from a nozzle by a valve at the nozzle, resulting in better control and a more constant product. One method of distribution of the foam is to disperse it in an airblast to be subsequently carried by the wind and spread for agricultural purposes.

United States Patent [72] Inventor Norman 11. Sachnlk [54] METHOD ANDMEANS FOR DISPERSING FOAM 2,61 1,439 9/1952 Faulkner 169/15 2,925,2222/1960 Spreng 239/77 2,979,269 4/1961 Bals 239/77 3,337,195 8/1967Farison 169/15 FORE1GN PATENTS 1,061,054 11/1953 France 169/15 1,128,9469/1956 France 169/15 Primary Examiner-Lloyd L. King AllorneyCharles W.Coffee 3 Claims, 6 Drawing Figs.

[52] 11.8. CI 239/8. 239/77, 239/343 [51] 1nt-Cl ..A0ln17/02,

A62: 1/12 ABSTRACT: Foam is generated by mixing water, foam Fleld ofSearch material and compressed air under pressure The foam is 169/15;239/77 343 released from a nozzle by a valve at the nozzle, resulting in56 R f ed better control and a more constant product. One method of 1 1e erences It distribution of the foam is to disperse it in an airblastto be UNITED STATES PATENTS subsequently carried by the wind and spreadfor agricultural Re.l9,965 5/1936 Schroderetal 252/3595 purposes.

AIR COMPRESSQR Q4 PATENTEDNOV 9 l97| 3.6 1 8,856

sum 1 [IF 2 AIR coMPREssoR Q4 FIG. I I GENERATOR SOURCE OF AIR 5 FOAMUNIT INVENTORI NORMAN H. SAOHNIK PATENTEDuuv 9 l97l 3,618,856

SHEET 2 UF 2 CHEMICAL 'TANK INVENTORI NORMAN H. SACHNIK BYI METHOD ANDMEANS FOR DISPERSING FOAM Applicants application Ser. No. 561,740, filedJune 30, 1966, now U.S. Pat. No. 3,368,183 entitled Method and ProductFor Agricultural Purposes discloses the use of foam such as produced bythe method of the instant application.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to foam generation and, more particularly, to generating anddispersing foam for agricultural applications.

2. Description of the Prior Art At present, foam is generated bymanydifferent methods, such as mixing air and fluid at the nozzle withor without the aid of mechanical agitation. Foam is sometimes generatedby mixing a gas and a liquid under pressure but without mechanicalagitation; a common example of this type is aerosol shaving cream orwhipping cream.

More generally, the foam is dispersed by its own force leaving thenozzle. It has been suggested by White, et al., US. Pat. No. 3,096,819,issued July 19, 1963, that the foam could be carried in a gas stream;however, in that application, the gas stream and foam were alwaysconfined within a string of pipe.

SUMMARY 1 have invented an apparatus which generates the foam bysupplying water and air both under pressure to a mechanical agitatorwhich agitates the products under pressure. From there, the mixture isconveyed under pressure through a conduit to a nozzle where it isreleased. When the nozzle is closed, pressure regulating valves preventan excessive buildup of pressure.

Also, to get a broadcast distribution and coverage, the foam is carriedin an airblast in addition to its own propulsion as it jets away fromthe nozzle.

An object of this invention is to produce foam.

Another object is to broadcast foam.

Further objects are to achieve the above with a device that is sturdy,compact, durable, simple, safe, versatile, and reliable, yet inexpensiveand easy to manufacture, operate, and maintain.

Still further objects are to achieve the above with a method that israpid and inexpensive and does not require skilled people to adjust,operate, and maintain.

The specific nature of the invention, as well as other objects, uses,and advantages thereof, will clearly appear from the followingdescription and from the accompanying drawing, the different views of.which are not necessarily to the same scale.

DESCRIPTION OF THE DRAWING FIG. 1 is a schematic representation of afirst embodiment of this invention.

FIG. 2 is a schematic representation of a second embodiment of thisinvention, particularly illustrating a model adapted to be mounted onaircraft.

FIG. 3 is a schematic representation of a modification for broadcastdistribution.

FIG. 4 is a perspective view showing the broadcast dispersion from adistance.

FIG. 5 is a sectional view of the mixing chamber of the foam generator.

FIG. 6 is a cross-sectional view taken substantially on line 6-6 of FIG.5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring more particularly toFIG. 1, water and a suitable foam material are mixed in tank 10. Foammaterials are well known and commercially available on the market and,therefore, will not be further described here.

As the ultimate purpose contemplated for the use of the foam isagricultural, at this point, the particular chemical to be applied alsowould be included in the tank 10. For example, if the material was to beused to kill brush, as described in my prior application identifiedabove, a herbicide would be mixed in the tank 10; if the foam materialwas to control insects, an insecticide would be mixed in the tank 10.

From the tank 10, the mixture is pressurized by pump 12. The pressure inwater pipe 14 on the outlet of the pump cannot exceed a predeterminedvalue because pressure relief valve 16 will relieve the pressure throughrelief line 18 back to the tank 10. The regular flow of fluid throughthe relief line 18 will act to agitate the fluid in the tank 10 andprevent separation of the materials therein.

Check valve 20 separates the water pipe 14 from mixing pipe 22. Thecheck valve permits flow from the water pipe to the mixing pipe butprevents reverse flow. Air compressor 24 forces compressed air into themixing pipe 22 through air line 26 through check valve 27. Air pressurerelief valve 28 limits the maximum pressure of the air into the mixingpipe. The outlet of the pressure relief valve 28 is directed to theinlet of the air compressor, viz., the atmosphere. The mixing pipe 22discharges the mixture of water, foam material, chemical, and air, allunder pressure, into foam generator 30.

In the foam generator, the mixture is thoroughly agitated or frothed byagitator 32. (FIGS. 4 and 5) The agitator is rotated by pulley 34 onshaft 36 which is connected to the agitator 32. The impeller from anautomotive water pump acts well as the agitator. However, it will benoted that there is no increase in pressure through the agitator, butthat the fluid is pushed through the generator by the pressure withinthe mixing pipe v22. Internal baffle 37, which is concentric with theshaft 36 and case 39 of the generator 30, provides internal circulationof the fluid mix in the case 39. Therefore, the fluid is more thoroughlyfrothed while flowing and also maintained in a frothed condition whenthe outlet is closed as described hereafter.

The outlet from the generator is connected to manifold 38 to which isconnected at least one nozzle 40. The flow of the foam to the nozzle 40is controlled by hand valve 42 at the nozzle.

In operation, the pump 12, air compressor 24, and agitator 32 areoperated continuously. When the valve 42 is open, the material underpressure in the manifold 38 and in foam hose 44 from the manifold to thevalve 42 is discharged as foam from the nozzle 40. The materialimmediately foams and there is no liquid flow initially when the valveis opened.

Pressure regulator valve 46 in the mixing pipe 22 limits the pressureupon the foam generator 30 when all the valves 42 are closed.

The equipment has worked well by setting the pressure relief valve 16 torelieve at 35 to 45 p.s.i. and the air pressure relief valve 28 torelieve at 40 to 50 p.s.i. and the pressure regulator valve 46 to limitthe pressure upon the generator 30 to 20 to 30 p.s.i. l have found theequipment described operates well with one nozzle 40 used intermittentlyor all three nozzles 40 used continuously. The proper flow of materialto the mixing pipe 22 is aided by fixed resistance or orifice 45 inwater pipe 14 and variable resistance or needle valve 47 in air line 26.

It will be understood that, in application with the embodiment shown inFIG. 1, the equipment would be mounted upon a vehicle, either a smalltruck or a specially constructed vehicle, and therefore operators foreach of the nozzles 40 would direct the foam upon individual plantsmanually. Also, it will be understood that use of foam has manyapplications other than its application to plants. The equipmentdescribed is adaptable for many other uses.

The embodiment of FIG. 2 is particularly adapted to be attached to anairplane for aerial distribution of foam. Waterchemical-foam materialmix in tank is pressurized into water pipe 114 by pump 112 driven bypropeller 113. From the pump 112, the mix goes through pressureregulator I16, orifice 145, and check valve into mixing pipe 122. Thereit is mixed with pressurized air from high-static pressure device 124through pressure regulator 128 in air pipe 125 and airflow control valve147 and check valve 127. High-static pressure devices are known to theart and are adapted to be mounted on the airplane exposed tohigh-velocity air. From the mixing pipe 122, the mix is frothed by foamgenerator 130 driven by propeller 131. From the generator, the frothedmaterial passes through valve 142 to nozzles 140 on wing boom 138 whichis adapted to be mounted under the wing of the aircraft.

The modification in FIG. 3 illustrates an alternate method ofdistributing the foam rather than by the use of a manifold with aplurality of nozzles. In FIG. 3, the foam is generated by foam unit 48the same as in the previous embodiments, i.e., foam unit 48 wouldinclude tank or 110, pump 12 or 112, air compressor 24 or 124, andgenerator 30 or 130. The frothed air-liquid mixture from the foam unitwould be discharged from a plurality of nozzles 50 in front of an airjet from horn 52. The flow of foam to the nozzles would be controlled byvalve 54. The air jet is produced by source of air 55 which could be afan and motor as described below or an air scoop similar to device 124.

In FIG. 4, motor 56 drives fan 58 to blow air into duct 60 whichdischarges it through the horn 52. The discharge from the horn isgenerally outward, although at the upper portions it will be upward asmuch as 27 from horizontal. The lower portion of the horn 52 willdownwardly direct the jet of air and foam therefrom. The nozzles 50 aremounted upon header 62 which is attached by suitable brace 64 to upperpart 66 of horn 52. The upper part 66 of the horn and the header 62 aremounted for rotation about a vertical axis so that the foam producedtherefrom may be directed in any one of several directions.

Referring more particularly to FIG. 4, the born 52 and the foam unit 48are adapted to be mounted upon a vehicle and the foam distributed as thevehicle slowly traverses one side of the area to be treated. The vehiclewould transverse to the windward side and the horn 52 directed downwind.The airblast from the horn 52 will carry globulets of foam forconsiderable distances. Also, what wind may be available will carry theglobulets of foam over quite a long distance. Therefore, a very largearea of land may be covered quickly and economically. Although the lightglobulets of foam will be carried long distances, they will come downwithin a more predictable area than a water mist. Chemicals carried in awater mist sometimes carry for a considerable, unpredictable distance.Inasmuch as herbicides are extremely harmful to certain crops, it isdesirable that the carry distance be predictable.

It will be apparent that the embodiments shown are only exemplary andthat various modifications can be made in operation, construction,materials, and arrangement within the scope of the invention as definedin the appended claims.

I claim as my invention:

1. The method of producing foam comprising:

mixing foam material with water, then supplying said water-foam materialmix to a mixing chamber under pressure,

controlling the flow of said water-foam material mix into the mixingchamber by a pressure regulator valve,

further controlling the flow of said water-foam material mix into themixing chamber by a restriction in the flow path,

simultaneously supplying air under pressure to said mixing chamber,controlling the flow of said air into the mixing chamber by a res onsive to operation of a valve located at the noule. 2. he invention asdefined in claim 1 with the additional limitations of:

continuously supplying water-foam material mix and air under pressure tothe mixing chamber independently of operation of the valve located atthe nozzle, and continuously operating the agitator in the mixingchamber independently of operation of the valve located at the nozzle.

3. The method of dispersing foam for application to plants comprising:

generating an airstream,

generating foam,

transporting the foam to the airstream,

dispersing the generated foam from nozzles in the airstream,

thereby breaking the generated foam into globulets by the airstream, and

carrying the globulets of generated foam in the airstream,

said foam being generated by mixing foam material with water, thensupplying said water-foam material mix to a mixing chamber underpressure,

controlling the flow of said water-foam material mix into the mixingchamber by a pressure regulator valve,

further controlling the flow of said water-foam material mix into themixing chamber by a restriction in the flow path,

simultaneously supplying air under pressure to said mixing chamber,

controlling the flow of said air into the mixing chamber by a pressureregulator valve,

further controlling the flow of said air into the mixing chamber by arestriction in the flow path,

also limiting the pressure in the mixing chamber by a pressure regulatorvalve thoroughly agitating the water-foam material mix and air underpressure in the mixing chamber.

1. The method of producing foam comprising: mixing foam material withwater, then supplying said water-foam material mix to a mixing chamberunder pressure, controlling the flow of said water-foam material mixinto the mixing chamber by a pressure regulator valve, furtherconTrolling the flow of said water-foam material mix into the mixingchamber by a restriction in the flow path, simultaneously supplying airunder pressure to said mixing chamber, controlling the flow of said airinto the mixing chamber by a pressure regulator valve, furthercontrolling the flow of said air into the mixing chamber by arestriction in the flow path, also limiting the pressure in the mixingchamber by a pressure regulator valve, thoroughly agitating thewater-foam material mix and air under pressure in the mixing chamber,thereafter transporting the agitated mixture to at least one nozzle,jetting the agitated mixture from the nozzle responsive to operation ofa valve located at the nozzle.
 2. The invention as defined in claim 1with the additional limitations of: continuously supplying water-foammaterial mix and air under pressure to the mixing chamber independentlyof operation of the valve located at the nozzle, and continuouslyoperating the agitator in the mixing chamber independently of operationof the valve located at the nozzle.
 3. The method of dispersing foam forapplication to plants comprising: generating an airstream, generatingfoam, transporting the foam to the airstream, dispersing the generatedfoam from nozzles in the airstream, thereby breaking the generated foaminto globulets by the airstream, and carrying the globulets of generatedfoam in the airstream, said foam being generated by mixing foam materialwith water, then supplying said water-foam material mix to a mixingchamber under pressure, controlling the flow of said water-foam materialmix into the mixing chamber by a pressure regulator valve, furthercontrolling the flow of said water-foam material mix into the mixingchamber by a restriction in the flow path, simultaneously supplying airunder pressure to said mixing chamber, controlling the flow of said airinto the mixing chamber by a pressure regulator valve, furthercontrolling the flow of said air into the mixing chamber by arestriction in the flow path, also limiting the pressure in the mixingchamber by a pressure regulator valve thoroughly agitating thewater-foam material mix and air under pressure in the mixing chamber.